1. Technical Field
The present disclosure relates to a circuit device, an oscillator, an electronic apparatus, and a moving object.
2. Related Art
In the related art, an A/D conversion circuit which performs analog-digital conversion (hereinafter, referred to as A/D conversion) for converting an analog signal to digital data is widely known. As types of A/D conversion circuit, there are various types such as a flash type, a successive comparison type, and a ΔΣ type. For example, JP-A-2011-223404 discloses a method of performing successive comparison type A/D conversion.
There are various circuits using temperature detection data which is a result of A/D conversion of a temperature detection signal (analog signal) from a temperature sensor unit. For example, in the related art, a temperature compensated crystal oscillator (TCXO) is known. The TCXO is used as, for example, a reference signal source or the like in portable communication terminals, GPS related apparatuses, wearable apparatuses, on-vehicle apparatuses, and the like. A technique disclosed in JP-A-64-82809 is known as related art for a DTCXO which is a digital type temperature compensated oscillator.
There is a request for outputting A/D conversion result data which is a result of A/D conversion at a high speed (in a short A/D conversion period). For example, in a digital type oscillator such as a DTCXO, an output oscillation frequency may be required to be stabilized in a short period of time, and, in this case, temperature detection data used for a temperature compensation process has to be output at a high speed.
However, JP-A-2011-223404 does not disclose a speed for A/D conversion. JP-A-64-82809 discloses an A/D converter using redundant conversion algorithm, particularly, an efficient test method thereof, and does not disclose a specific method of achieving a high speed.